This invention relates to the art of welding and, more particularly, to the encoding of metal welding wire with information pertaining thereto, and to the monitoring and/or controlling of automatic or semi-automatic welding apparatuses and processes based on the information extracted from a coded welding wire or from other electronically readable information storage devices encoded with information pertaining to a given welding wire.
The present invention is particularly applicable to the encoding and use of coded filler wire and other electronically readable information storage devices in connection with controlling automatic or semiautomatic arc welding apparatuses and processes based on information pertaining to the welding wire. Accordingly, the invention will be described with reference to such welding wire information and the storage and use thereof in conjunction with manual and/or automatic control of a welding process or apparatus.
Electric arc welding is a complicated process wherein numerous interrelated and non-interrelated parameters affect the deposition of molten metal to a weld pool in performing a welding operation. One such parameter is the welding wire to be used and, in particular, information pertaining thereto which is useful, for example, in determining processes and apparatuses in which its use is best suited and processes and/or apparatus operating parameters for a given wire. Other information, such as the date and time of manufacture, the manufacturing location and the like, can assist in tracing the origin of the wire should a problem occur requiring contact with the manufacturer. Further, information such as the alloy type, wire diameter, control numbers, lubrication levels, and the like is valuable for controlling a given process or apparatus so as to optimize performance and weld quality.
In particular, the quality of automated welding is significantly affected by variations in the welding wire diameter which can vary by +/−0.001 inch and still be within welding wire specifications, and such a variation can change the deposition rate by as much as six percent for 0.035 inch diameter wire. Welding wire is drawn, and such diameter variations result from a manufacturer's efforts to fully extend the life of a die by starting with a die that produces slightly undersized wire within a given specification. The die progressively wears during production, whereby the wire size gradually increases and eventually becomes oversized with respect to the specification. While it is possible to tightly control the wire diameter during production such as by frequent replacement of dies, such production for most practical purposes is economically unacceptable. Another major factor affecting weld quality is a variation in the proportion of major to minor gases in the shielding gas mixture for GMAW or MIG welding. The variation of the proportion of the minor gas from a given standard therefore can significantly alter the heat input and thus the weld size, shape and quality. Still another factor affecting weld quality and/or the efficiency of the welding process is the amount of a consumable that remains during a welding process. Consumables such as the welding wire and shielding gas are consumed during a welding process. During an automatic or semi-automatic welding process, the welding process may not be closely monitored by an operator. As such, one or more of the consumables may be used up during a welding process thereby adversely affecting the weld quality. For instance, when the weld wire is fully consumed, further formation of a weld bead does not occur. Furthermore, when the shielding gas is fully consumed, the weld bead quality of the formed weld is adversely affected. In addition, when one or more consumables is fully used, the welding operation has to ultimately stopped and the consumable replaced. The stopping of the welding process reduces welding efficiencies due to unanticipated down time and can also result in partially welded workpieces having to be discarded.
In view of the state of the prior art, there is a need for a welding monitoring and/or control system to improve the efficiencies of automatic and/or semi-automatic welding processes and the quality of a formed weld bead.